Will Haltom

Yeah this issue makes stepping and `finish`ing quite slow for large callstacks. I think those ^ PRs should help quite a bit, with both changes together I measured a ~99%...

Gotcha, yeah #743 makes the most difference when the ratio of :line to :return is flipped.

> The `on_load` event also [stores loaded files into the SourceRepository](https://github.com/ruby/debug/blob/2cb44483c681f6806bf6843a8f996d3a10d0e42c/lib/debug/session.rb#L1606), which will later be used to display [frames' file_lines](https://github.com/ruby/debug/blob/c35bd4cad98229419d56ecd6ceb5e1a266a959f5/lib/debug/frame_info.rb#L67-L69). So skipping them will likely cause `list` command to return...

> Yes I think you get it right. I missed the fallback mechanism. @st0012 thanks for the feedback! Based on that ^, does the approach in https://github.com/ruby/debug/commit/949562dda5b6ead980bc19540fed6a76452e0dea seem alright? Alternatively,...

@ko1 I've updated this in https://github.com/ruby/debug/pull/738/commits/0e12fa193a5b6c30ba714dfd0d053577d20163b3 to only skip it on Ruby 3.1 and later 👍

@st0012 thanks for the feedback! That's a great refactor, I did that in https://github.com/ruby/debug/pull/743/commits/7a414919c42e1a9cc3854071cc2488e945bedcb3 👍

> Could you measure the time with #746 ? @ko1 yes, here is that result: Using the same example as above ```ruby # target.rb def foo "hello" end def recursive(n,stop)...

> Ah, I'm sorry I need to ask you that "with #746 but without #743". I will merge #746 but I need to read details of #743 for review. But...

> Ah, I found an issue, it doesn't support multi-threads, so I'll revert it. Sorry. Ah, no problem, I agree with > It seems #746 is dominant anyway. Is it...

@ko1 Yeah, currently this will only work for ruby 3.0 and up > Note Currently, this approach will only work with ruby >= 3.0. It appears that for ruby <...